As far as I know there is only the current (vanilla+plugins) server. The poll for the tekkit server is still up, but it states that if they want to implement it, it will be probably done not until 1.3 comes out.
hope it helped.

You could take a look at the planes mod
http://www.minecraftforum.net/topic/182918-125flans-mod-rewritten-and-now-totally-awesome/
It's technical, it fits the industrialized theme and makes travelling around easier.

Hi everybody.
Maybe it's a good idea to share when you started playing Minecraft, and how you discovered the game. Maybe you've only played it for a month, or you're an alpha veteran. It could be you once saw a video on Youtube, or one of your friends played it. Share your story below.
I've played it since beta 1.3 (I think, only thing I remember from those days is my first map I spawned next to a dungeon and spiders kept on killing me). I followed let's plays on the internet and came across a let's play of Minecraft. And thought: I want to try that for myself. The rest is history...

Maybe a silly question, but as it stands now, will it be a server with vanilla minecraft play (gathering blocks, building your home and go on an adventure) or purely building?
I'm asking this because I don't have much experience with servers, and the few I've visited where purely building servers. While sometimes it can be fun to play as creative mode, it takes away a bit of fun in the long run.
Maybe this question has been answered before, but I could't read it anywhere.